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By Daniel Fischer Every page present in Europe & the U.S.!
| Ahead | Awards 
The latest issue!
| A German companion! (SuW version) Current mission news: MGS (latest pictures!) + Cassini + Galileo + NEAR |
on the evening of July 23rd: Science@NASA, lots of eyewitness reports, DoD Release, APOD and coverage by Reuters, Astronomy, CNN (earlier), ABC ( earlier), MCall (earlier), WP, SF Gate, Phil. Inq., SC, BdW, DPA. The outlook for the Perseids this month isn't great: Science@NASA. Forecasts for the Leonids stay bright: SC. What the Tunguska impact would have looked like, as reconstructed by planetary scientist & space artist W. Hartmann. NEAR lands on Eros - the movie: JHU APL Press Release, the movie, SC, CNN, SPIEGEL.
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Radio telescopes image coronal mass ejection in great detailAstronomers have made the first radio-telescope images of a powerful coronal mass ejection on the Sun, giving them a long-sought glimpse of hitherto unseen aspects of these potentially dangerous events. They used a solar radio telescope in Nancay, France, to study a coronal mass ejection that occurred on April 20, 1998. Coronal mass ejections have been observed for many years, but only with visible-light telescopes, usually in space. While previous radio observations have provided us with powerful diagnostics of mass ejections and associated phenomena in the corona, this is the first time that one has been directly imaged in wavelengths other than visible light.These new data from the radio observations provide important clues about how these very energetic events work: The radio images show an expanding set of loops similar to the loops seen at visible wavelengths. The radio loops, astronomers believe, indicate regions where electrons are being accelerated to nearly the speed of light at about the time the ejection process is getting started. The same ejection observed by the radio telescope also was observed by orbiting solar telescopes. Depending on what later radio observations show, the solar studies may reveal new insights into the physics of other astronomical phenomena.
For example, shocks in the corona and the interplanetary medium
accelerate electrons and ions, a process believed to occur in supernova
remnants - the expanding debris from stellar explosions. The radio
detection of a coronal mass ejection also means that warning of the
potentially dangerous effects of these events could come from
ground-based radio telescopes, rather than more-expensive orbiting
observatories. With solar radio telescopes strategically placed at
three or four locations around the world, coronal mass ejections could
be detected 24 hours a day to provide advance warning.
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Solar sail test ends in failure, but the orbital test shall go aheadA suborbital test of "Cosmos 1", the first spacecraft to try out solar sailing (see Update # 219 story 2) has failed on July 20th: The final command to separate the spacecraft from the submarine-launched Volna rocket was not executed. As a result, neither the solar sail deployment test nor the re-entry capsule inflation sequence that were planned for this sub-orbital test flight were carried out. The spacecraft and the unseparated capsule continued together to impact in Kamchatka. Telemetry from the launch vehicle indicated the separation failure. The Makeev Rocket Design Bureau engineers are analyzing the data to determine exactly what happened and why.The capsule recovery team stationed in Kamchatka is reported to have observed the re-entry. Makeev is now responsible for locating the probably destroyed capsule and spacecraft in Kamchatka. A very preliminary examination of the rocket telemetry data in Russia indicates that the separation command was terminated by an on-board fail-safe program because dynamic variations were sensed in the third stage; the launch vehicle was pre-programmed to override the separation command in the presence of dynamic variation. Despite the setback the Planetary Society is ready to push ahead with its plans, with the real orbital test hardly slipping and perhaps even another suborbital test before that. |
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Lost Japanese X-ray satellite will be re-built!The United States and Japan will team up to rebuild and launch a powerful observatory for measuring high energy phenomena in the Universe. The Astro-E2 observatory will replace the original Astro-E satellite, which was lost during launch in February 2000 (see Updates # 174 story 2 and 178 story 6). The Japanese government recently approved the Astro-E2 mission and has invited NASA to participate. Scheduled for launch in February 2005, the instruments on Astro-E2 will provide powerful tools to use the Universe as a laboratory for unraveling complex, high-energy processes and the behavior of matter under extreme conditions.These include the fate of matter as it spirals into black holes, the nature of supermassive black holes found at the center of quasars, the 100 million degree gas that is flowing into giant clusters of galaxies, and the nature of supernova explosions that create the heavier elements, which ultimately form planets. NASA will provide the core instrument, the high resolution X- Ray Spectrometer (XRS). The XRS will be the first X-ray microcalorimeter array to be placed in orbit. It measures the heat created by individual X-ray photons. |
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Artemis rescue under way, orbit circular at 31 000 kmA recovery strategy has been put in place to bring the stranded satellite to the nominal geostationary position and to maintain chemical propellant and xenon (the gas used for the electrical ion-propulsion system) to maximise the lifetime of the spacecraft, originally planned to last 10 years. In a first step the apogee boost motor (using chemical propulsion) was operated during several perigee passes to increase the apogee to about 31 000 km, while the perigee was not raised by very much. The elliptical orbit was then circularised by a number of apogee and perigee manoeuvres resulting - on July 24 - in a quasi-circular parking orbit with the satellite at 31 000 km above the Earth and an orbit duration of about 18 hours.On completion of this step, the solar arrays will now be fully deployed, as will the antenna reflectors. The satellite will then be in nominal mode, while not yet in geostationary orbit. The satellite will then be "spiralled" from the parking orbit to the nominal geostationary orbit using the satellite's electrical ion-propulsion system - this is expected to start at end of September and will last several months. This recovery scenario is the one which offers the best chances of bringing the satellite from the degraded injection orbit to the nominal geostationary position and saving enough chemical fuel and xenon to support some years of nominal operation.
Ariane 5 malfunction called "serious"The upper stage of the 10th Ariane 5 failed to deliver its full thrust and shut down early on July 12th, and both satellite payloads were delivered into orbits that were too low - while the European Artemis satellite might be able to rescue itself with its engines, Japan's BSAT-2b is probably lost. Both satellites were separated on an orbit of 17,528 km apogee, 592 km perigee and 2.9 degrees inclination for a targeted orbit of 35,853 km apogee, 858 km perigee and 2 degrees inclination. From the start of its ignition, the German-made upper stage had provided 20 percent less thrust than planned, and instead of compensating that by burning longer, the stage shut down 80 seconds before the scheduled end of its 16 minute, 20 second burn. Analysts call the incident "a serious failure for Arianespace" that "could affect its market prospects and future insurance rates." And "in addition to cost and market implications, the malfunction will also raise major policy issues in ESA which abandoned a launch on the new unproven Japanese H/IIA, when the $850-million Artemis ran into huge development cost overruns." (AW&ST of July 16 p. 22) |
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Futuristic astronomical camera produces first resultsA totally new type of optical detector has been used on the William Herschel Telescope to directly measure intensity and colour changes in a faint, rapidly variable binary star system, UZ Fornacis, for the first time. With conventional optical CCD detectors, very rapid changes in light intensity cannot be measured. Furthermore, the energy or wavelength of the arriving photons can only be measured by introducing a filter or spectrograph into the optical light path, degrading the efficiency. With the new instrument called Superconducting Tunnel Junction Camera or S-Cam, advanced detector elements based on superconducting technology register the arrival of each photon individually, and measure its energy and wavelength directly. In the particular binary star system studied, one of the two stars is a so-called white dwarf, a star in an advanced state of stellar evolution that collapses slowly under its own gravity. This white dwarf tears gas from the surface of its nearby companion, which is then engulfed by the white dwarf's powerful gravitational field.
Three ESA scientists published the theoretical ideas underlying the new detector
in 1993, the first instrument able to detect the energy of optical photons
directly. The first detection of optical photons using this technology was
reported in 1996, and S-Cam, the first real scientific instrument making use
of these principles and developed by the same research team, was commissioned
at the William Herschel Telescope in February 1999. S-Cam is equipped with an
array of 6 W 6 small chips of the metal tantalum, cooled with the help of a bath of
liquid helium to a temperature within a degree of absolute zero. Incident photons
break Cooper pairs responsible for the superconducting state, and since the energy
gap between the ground state and excited state is low, each individual photon
creates a large number of free electrons, in proportion to the photon energy -
thus by measuring the charge released by each detected photon, these can be
sorted in energy.
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ISS UpdateAtlantis has completed mission STS-104, in which the crew has installed an airlock which will permit EVAs with American spacesuits without the presence of a shuttle - and the ISS-bound launch of Discovery has been confirmed for August 9: STS-105 Press Kit. STS-104 Mission Journal, Status Center, MCC Status Reports # 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, KSC Release, NASA Release, Science@NASA of Aug. 2, July 25 and July 23.Coverage of August 2: ST, FT. Aug. 1: ST. July 31: ST, Reuters, FT. July 29: SD. July 27: SC, AP. July 26: SC, FT, SPIEGEL. July 25: SN, BBC, FT, CNN, SC, NZ, RP, SPIEGEL. July 24: FT, CNN, ST, AN, SC, RP. July 23: SC. July 22: CNN, SC, BBC, ST, RP. July 21: SN, SC, BBC, CNN, ST, FT, AP, RP, DPA, SPIEGEL. July 20: SC, OS, HC, AP. July 19: HC, FT. |
July 18:
SN,
HC,
SC,
AN,
ST,
CNN,
BBC,
RP,
SPIEGEL.
July 17:
SC,
HC,
ST,
CNN,
RP.
July 16:
HC,
CNN,
SC,
SPIEGEL.
July 15:
SN,
AFP,
ST,
BBC.
July 14:
FT,
SN,
ST,
AFP,
AP,
SPIEGEL.
July 12:
APOD,
SN,
HC,
BBC,
SC,
OS,
CNN,
AN
(
other story), ST,
FT
(
earlier),
Guardian,
AW&ST,
RP,
SPIEGEL.
July 11:
AFP
(other
story),
FT
(
other story),
SC.
July 10:
AFP,
AN,
SC,
NYT,
New Sci.
July 9:
AW&ST.
Another "space tourist" in training in Russia, ISS visiting rights requested: SC ( earlier), AW&ST, AFP, BBC. House panel restores funds for CRV - a Republican-led House budget panel has parted ways with the White House by adding $275m to NASA's 2002 spending plan to cover construction of a crew lifeboat for the ISS: SN, ST, HC, SC. Another X-38 test: SC. Columbia close to retirement? Rising costs in NASA's shuttle program could make Columbia's planned flight next May its last: OS, SC. |
U.S. Senate finds money for Pluto space probeA U.S. Senate committee approved a NASA budget that includes $25m for a Pluto mission by taking an equal amount away from a program to develop advanced propulsion technologies for a future Pluto mission: SN, SC, ST. Controversies brewing: SD, SC. House approves $14.9b for NASA: FT. ESA's science program reviewed by SD.More on the great dust storm on Mars(see last Update small items) from TES on MGS (here is how the dust spread, as a picture series of one hemisphere and the other and as a movie), JPL, Science@NASA, ASU. Coverage by CNN, SC, FT, NZ, RP, SPIEGEL. The ongoing amateur observations are documented in the US and in Japan, with all the images here! Molecular hydrogen detected on Mars: IAUC.Signature of life on Mars claimed in Viking lander data - something in the collected soil seems to have been metabolizing nutrients with a distinct biological rhythm pointing to a living cell: USC Release [SN], New Sci., SC, ENN, Sci. Am., SPIEGEL, MorgenWelt, NZ, AstroNews. Largest flood channels in the solar system found on Mars: UA News, BBC, SC. Evidence of icy region and recent climate change observed on Mars: Brown Release [SR], ST, SC, AP, BBC, RP. Liquid water on Mars in recent times? UA News, SN. MGS observations of Martian ice clouds: NSU, Astronomy. 25 years ago Viking 1 landed on MarsA reason for NASA and others to celebrate: JPL Release, Science@NASA, CNN (other angle), FT, SC ( other story). Viking 2 lander named after Soffen: SC.Mars Odyssey passed half-way point on trip to Mars: Mission Status. Preparing for the 2003 Mars rovers: FT. MRO, the next orbiter after Odyssey in 2005: SC. Contracts awarded for Mars Ascent Vehicle concept studies: JPL Release. Cassini's Jupiter pics turned into videoA movie made from about 1,200 Jupiter images taken by Cassini reveals unexpectedly persistent polar weather patterns on the giant planet: JPL Release [alt. version], PIA 345... 2, 3, 4, BBC, Reuters, NZ, SPIEGEL.Callisto's watery secret - the Jovian satellite's icy crust may be the planetary equivalent of a blanket, insulating an underground ocean: NSU, ST, BBC, SC. Galileo's next adventure - flying of Io's N pole on Aug. 6: JPL Release, CNN. Eilene Theilig, Project manager, Galileo Millennium Mission, in a long CNN portrait. Saturn's recently discovered moons fragments of larger ones? The 12 new-found moons are in irregular orbits that suggest they are the collisional remnants of larger parent moons, once securely captured in, but later blasted from, their saturnian orbits: UA News, NSU, SC, CNN, Astronomy, RP, SPIEGEL. No supermassive black hole in Messier 33HST spectra exclude anything heavier than 3000, perhaps even 1500 solar masses in the center of this spiral galaxy, apparently breaking a "law" linking the bulges of big galaxies and of their central engines: papers by Merritt & al. and Gebhardt & al., a Rutgers Press Release and coverage by SC and Bergen Record, SPIEGEL.Optical light from a hot stellar corona detectedAn optical coronal line from iron ions that have lost 12 electrons (Fe XIII) has for the first time been observed in a star other than the Sun - the object, a cool star named CN Leonis, is located at a distance of 8 light-years: ESO Press Release, NSU, Astronomy, SC, SPIEGEL.Magnetic stars can have rings - old IUE data confirm a long-suspected link between rings and magnetic fields; rings around massive stars should be even more common than scientists thought: STScI Release, SC. Red dwarf discovered just 6 parsec from the Sun - LHS 2090 was discovered from the combination of old high proper motion catalogues with a new near-infrared sky survey (2MASS) and follow-up spectroscopy: AIP Pic of Month. Galactic racecourse leads to ring of star formationRemarkable Hubble Space Telescope images of a star-forming ring in the disk of a distant galaxy directly show the shape of the orbit traced out over time by gas and newly formed stars. Just like cars on a flat oval race track, when these clouds reach the more sharply curved ends of the ellipse, they slow down and may bump into each other - this leads to formation of young star clusters that are observed to be concentrated around the ends of the ellipse: Alabama News.A wind bubble around a young super star cluster where stellar winds are pushing around millions of earth masses of gas has been found in the galaxy NGC 5253 - the cluster and its windy cocoon emit the power of a billion suns and are responsible for almost 1/4 of the entire energy output of the galaxy: Press Release (in PDF) and pictures. Case for "close" LMC strenghtens againOnce again a pretty direct method of stellar distance determination has yielded a "short" value for the Large Magellanic Cloud: A third eclipsing binary in this galaxy, EROS 1044, indicated a distance modulus of 18.3 mag., in agreement with the value derived from the two earlier cases (see Update # 193 for details and the technique). Thus the case strengthens for the LMC being some 8% closer to us than the often used 50 kpc - which would also make it necessary to raise the "final" value of the Hubble constant (see last Update story 1 sidebar) accordingly: Maloney & al., conference poster (in PDF). |
Water-bearing worlds dying with their sun?As an alien sun blazes through its death throes, it is apparently vaporizing a surrounding swarm of comets, releasing a huge cloud of water vapor, observations with the Submillimeter Wave Astronomy Satellite (SWAS) indicate - the data provide the first evidence that extra-solar planetary systems contain water: papers by Melnick & al. and Ford & Neufeld, SWAS Press Release and more plus Science@NASA. Coverage by HC, CNN, BBC, WP, New Sci., APOD, SC, SPIEGEL, WELT.Another discovery in the same star's envelope is an exotic new chemical compound, aluminum isocyanide (AlNC), identified on the basis of radio signals that the molecule emits at millimeter wavelengths - the discovery has important implications for the processes by which heavy elements like aluminum enter the interstellar medium: Univ. of AZ Press Release. Wave structures in a planetary nebulahave been revealed by the HST in the "Spider Nebula" NGC 6537 - these waves are driven by stellar winds radiating from the hot central star, much as a wind passing over a lake can generate waves on the water: ESA HST Release, CNN, APOD, SC, SPIEGEL.Jet-like mass ejections in a dying star have been imaged by the HST in the "Frosty Leo Nebula" - an example of the extraordinary and puzzling symmetries which characterise the ejection of matter during the death of Sun-like stars: Press Release. Gemini spies strong stellar gusts in nearby massive star, AFGL 2591, thanks to its infrared vision: NOAO Press Release, BBC, SC. VLBA maps magnetic field in star-forming cloud in great detail: NRAO Press Release. Hubble photographs warped galaxyThe Hubble telescope has captured an image of an unusual edge-on galaxy, revealing remarkable details of its warped dusty disk and showing how colliding galaxies spawn the formation of new generations of stars: STScI Release, CNN, SC.Star clusters born in collisions in Stephan's Quintet, as revealed by the HST - arising from the wreckage are more than 100 star clusters and several dwarf galaxies: paper by Gallagher & al., STScI Release, CNN, SC, SPIEGEL. An HST panorama of the super-star cluster R 136 in the LMC, "the most spectacular cluster of massive stars in our cosmic neighborhood of about 25 galaxies": STScI Release. An HST image of a double star cluster, NGC 1850, in the LMC: ESA HST Release, STScI Release, JPL Release, CNN, BBC, SC, SPIEGEL. Cosmology supercomputer turned onUK cosmologists now have the entire Universe at their fingertips - the country's most powerful academic supercomputer has been switched on, giving researchers unprecedented freedom to model the cosmos with 152 processors that can perform 10 billion calculations per second: Univ. of Durham Release, Virgo Cons. HP, BBC, Reuters, NZ.Satellites keep an eye on Etna's eruptionSeveral earth observing satellites are tracking the development of the ash and sulfuric acid plumes from the active Sicilian volcano and their environmental effects: ESA, JPL [SN] and DLR releases, the plumes in 3D and coverage by BBC and SC.Publication of the SRTM maps begins after delays in calibrating the Shuttle radar data: SRTM Homepage, RP, SPIEGEL. ERS-1 was launched 10 years ago - the data from that ESA radar satellite as well as ERS-2 have led to over 30,000 scientific papers: ESA Press Release. Pioneer 10,11 'deviation' explicable without New PhysicsNon-isotropic radiation from the spacecraft could very well explain the deviation of their trajectories (see Update # 224 small items), so no speculative additional force needs to be invoked after all, the latest calculations indicate (without solving the problem in detail yet): paper by Scheffer.Gamma-ray bursts caused by electromagnetic black holes? Could be the first evidence of the explosive extraction of energy from an electromagnetic black hole: ICRA Press Release, SC. GRB detector-carrying Indian satellite reenters: SD.
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All other historical issues can be found in the Archive.
The U.S. site of this Cosmic Mirror has been visited
since it was issued (the German site has no counter).
Compiled and written by Daniel Fischer
(send me a mail to [email protected]!), Skyweek
